GRAZING PRESSURE IMPACTS ON POTENTIAL FORAGING COMPETITION BETWEEN ANGORA-GOATS AND WHITE-TAILED DEER

Increased Angora and Spanish goat populations in the Tamaulipan Provin ce of southern Texas and northeast Mexico and the economic importance of white-tailed deer lease hunting in the region has heightened concer n as to negative interactions between these two herbivores. This study selected a shallow ridge range site, dominated by palatable shrubs, a s a high potential community for herbivore interaction at the landscap e level. The site was stocked at 0, 2, 4, 6 goats/ha on an experimenta l ranch in South Texas. Deer and goat biting tactics, diet selection a nd reconstructed dietary crude protein and digestible organic matter w ere compared across stocking treatments. Dietary overlap indices were 0.75-0.88 between the herbivores across season and stocking rate. Deer had a greater tendency to use nip bites than goats in the non-grazed pastures (60-65% vs. 42-55%, respectively). However, goats increased t he use of nip bites more than deer as intraspecific competition increa sed while deer used similar strategies across all stocking rates. Incr eased stocking rates had little impact on dietary composition of woody species in the diet of goats. The greatest dichotomies of dietary sel ection between both herbivores was shrubby bluesage where deer exhibit ed a positive preference while goats generally avoided the species, re gardless of its availability. Both herbivores were generally able to s tabilize nutrient concentration in their respective diets regardless o f grazing pressure by goats.